Homebrew parkerizing actually worked!
I tinkered with making my own homebrew manganese parkerizing solution. I did research on the web and found some ideas and a lot of different-but similar recipes.
The web info listed using products that contained phosphoric acid, but those recipes were from the last decade when acid concentrations were higher, and have since changed in this "greener" climate. I had to do some more research on local products and MSDS sheets.
I found a gallon of Krud Kutter Concrete Cleaner and Etcher (<40% acid) for a whopping $12.99 at Menards! I also lucked out in having a local potter/pottery instructor in having manganese dioxide for $3.00 a pound-no taking apart batteries--if you ever do, make sure they are NOT alkaline- they spew nasty caustic chemicals!
I started the one gallon formula with two ounces of manganese dioxide powder which gave the results in the pics below. I found that the powder did not dissolve very readily and ended up with a lot floating around and settling on the bottom. I did do my Ishapore refurbish using this formula since I knew it worked. The reciever did not finish as dark, except for a ring around the locking lug recess where they have heat treated it. The barrel and other parts match those below.
Attachment 17439
(test parts from a Lee Enfield in.303 British)
I since changed the formula by reducing the manganese dioxide to 1 ounce per gallon. Those test pieces came out just as the others.
My formula (use at your own risk and test on your own!!)
120 fluid ounces distilled water (I used reverse osmosis water)
8 fluid ounces Krud Kutter Concrete Cleaner & Etcher (<40% phosphoric acid)
1 ounce manganese dioxide
0.5 ounces (1 coarse steel wool pad) iron scrap
Some recipes call for iron filings like those sold through Brownells. I found an ample supply (5 pounds) at the local Ford dealership at the brake turning machines. I also found the clean steel wool pads at Menards that were pretty clean of oil. If you use steel wool, make sure they are degreased of all oil.
My technique (I studied the instructions from Brownells which is available online):
Have all you parts degeased and blasted to a nice clean even finish. Use rubber gloves and hang them on degreased black rebar tie wire. Spray down a final time with brake cleaner.
1. Ready a large stock pot with clean fresh water and bring to rolling boil.
2. Ready another stainless steel stockpot with 120 ounces of distilled water.
3. Raise distilled water to about 140 degrees and add the 8 ounces of acid to the water.
4. Add the 1 ounce of manganese dioxide powder and stir thoroughly.
5. Raise the temp to about 180 degrees and add the steel wool pad. Keep stirring and submerge the pad as it will have the tendency to float after a few minutes. It will gas and and create a foam on the surface. Keep the pad in for 10 minutes, then remove. It should be black.
6. Submerge the parts in the boiling WATER for about 3 minutes.
7. Remove from the water and submerge in the park solution. Keep the solution moving and raise/lower the parts in and out of the solution one in a while to monitor the work and to keep slurry off the tops. Hang the parts from a rod so they are suspended in the soultion and off the bottom. Don't let them touch one another.
Keep the solution between 185-200 degress and do not let it boil--ever!
8. After 10 minutes (which worked for me), but no longer than 15, remove the parts from the park solution to the boiling water again. (Time varies on submerging the parts- keep an eye on it keep from etching.) My parts came out very black but had a coating of "sludge" on them.
9. After 3 minutes in boiling water, remove and spray down with WD-40.
10. After all parts are done, brush liberally with clean motor oil.
11. After a day, lightly scrub the parts with more oil and a soft tooth brush. I then lightly rubbed them with 0000 steel wool to remove all traces of sludge.
12. Apply gun oil and reassemble.
I figure I can make about 16 gallons of solution for about $17 (acid, manganese, and steel wool). Two gallons was more than enough to do my Ishapore 2a .308
I found about 3 weeks later I could reuse the same solution after it had cooled. I had made up an extra gallon a day later after the others to do a forgotten part. I let this solution sit in the SST pot. During this 3 week time it froze solid for about one week in subzero temperature. When I thawed it, it was "half" frozen. I placed it on the stove and warmed it back to 190 degrees slowly. The solution worked just as it did before with the other parts.
Here is my new shutterfly site for all the pics: http://cheese1566gunsandstuff.shutterfly.com/27/